| Luminara Education Trust | Education | 2014 |
| Lumi’S Car Repairs Ltd | Wholesale & retail | 2024 |
| Lumline Limited | Construction | 2025 |
| Lumora Jewellery Ltd | Wholesale & retail | 2025 |
| Lumos Property Solutions Limited | Real estate | 2024 |
| Lumrah Ltd | Professional & scientific | 2025 |
| Lumsden Living Limited | Administrative & support | 2009 |
| Luna Bidco Limited | Financial services | 2021 |
| Luna Cafe Ltd | Hospitality | 2022 |
| Luna Commercial Furniture Ltd | Wholesale & retail | 2019 |
| Luna Consulting Ltd | Construction | 2024 |
| Luna Drywall Ltd | Construction | 2023 |
| Luna Midco Limited | Financial services | 2021 |
| Luna Topco Limited | Financial services | 2021 |
| Lunchfield Lane Management Company Limited | Households | 1994 |
| Lunevia Ltd | Wholesale & retail | 2026 |
| Lungu Limited | Transport & logistics | 2015 |
| Lunservices Ltd | Construction | 2024 |
| Lunteam Limited | Real estate | 2023 |
| Lunu Construction Ltd | Construction | 2023 |
| Luoana Construction Ltd | Construction | 2024 |
| Lupul Singuratic Limited | Transport & logistics | 2025 |
| Lusherrie Limited | Information & communication | 2024 |
| Lushington Limited | Real estate | 2013 |
| Lushni Limited | Information & communication | 2019 |
| Luther LEE Couriers Service Ltd | Transport & logistics | 2025 |
| Luton Training & Mentoring Ltd | Other services | 2003 |
| Lutterworth Magna Park Truck Wash Ltd | Other services | 2026 |
| Lutterworth Residents Management Company Limited | Real estate | 2019 |
| LUX Construction Group LLP | | 2007 |
| LUX Developments (Northampton) Ltd | Construction | 2019 |
| LUX Emisso Ltd | Professional & scientific | 2024 |
| Luxe Global Trading Ltd | Wholesale & retail | 2017 |
| Luxe LAB Academy Ltd | Education | 2025 |
| Luxe Skin LAB Limited | Other services | 2025 |
| Luxe Venetian Design Limited | Construction | 2023 |
| Luxe Vertex Ltd | Wholesale & retail | 2026 |
| Luxesonic Production Ltd | Information & communication | 2024 |
| Luxivon Ltd | Wholesale & retail | 2026 |
| Luxon Micro Ltd | Professional & scientific | 2025 |
| Luxora Property Living Ltd | Real estate | 2026 |
| Luxora Rentals Ltd | Real estate | 2025 |
| Luxtosuit Ltd | Wholesale & retail | 2024 |
| Luxury Detailing Ltd | Wholesale & retail | 2025 |
| Luxury Hair Ltd | Wholesale & retail | 2020 |
| Luxury Property Expert Ltd | Real estate | 2022 |
| LV Interiors Limited | Construction | 2019 |
| LVC Management Ltd | Professional & scientific | 2025 |
| LVI Trans Ltd | Transport & logistics | 2021 |
| LW Gates and Barriers Limited | Administrative & support | 2025 |
| LX Car Sales Ltd | Wholesale & retail | 2026 |
| Lydian UK Holdings Ltd | Financial services | 2022 |
| Lydox Properties Ltd | Real estate | 2023 |
| Lykos Services Limited | Construction | 2021 |
| Lymington Marine Sales Limited | Wholesale & retail | 1999 |
| Lymited Ltd | Information & communication | 2019 |
| Lynch Scaffolding Services Ltd | Construction | 2026 |
| Lyncrest Properties Limited | Real estate | 1988 |
| Lyndon Agri Contracting Limited | Agriculture & fishing | 2023 |
| Lynn Haven Limited | Health & social care | 2024 |
| Lynsey Cosford Ltd | Information & communication | 2019 |
| Lynx Powertech Limited | Extraterritorial | 2000 |
| Lynxzeen Limited | Wholesale & retail | 2026 |
| LYS Beauty Ltd | Wholesale & retail | 2025 |
| LYW Property Ltd | Real estate | 2026 |
| Lyzon Associates Limited | Information & communication | 2019 |
| LZ Consulting Ltd | Other services | 2010 |
| LZR Express Ltd | Transport & logistics | 2022 |
| L’Amoré Nails & Beauty Ltd | Other services | 2025 |
| M & a 05 Ltd | Construction | 2017 |
| M & B Commercials Ltd | Wholesale & retail | 2018 |
| M & B Roofing & Cladding Ltd | Construction | 2013 |
| M & D Automotive Ltd | Wholesale & retail | 2024 |
| M & L Enterprises Limited | Information & communication | 1995 |
| M & M (MK) Investments Holdings Limited | Financial services | 2022 |
| M & M (MK) Limited | Financial services | 2001 |
| M & M Roofing Supplies Ltd | Wholesale & retail | 2014 |
| M & M Supplies (UK) PLC | Wholesale & retail | 2001 |
| M & M Supplies UK Holdings Limited | Financial services | 2022 |
| M & M Timber and Building Supplies Limited | Wholesale & retail | 2003 |
| M & P Carter Livestock Limited | Wholesale & retail | 2018 |
| M & R Refrigeration Limited | Administrative & support | 2004 |
| M & R Services (UK) Limited | Other services | 2003 |
| M & W Brickwork Limited | Construction | 2022 |
| M a Pandit & Co Limited | Manufacturing | 2019 |
| M a Shahid Investments Limited | Real estate | 2020 |
| M ALI FX Limited | Professional & scientific | 2023 |
| M and KAY Transport Ltd | Transport & logistics | 2016 |
| M and S Union Limited | Construction | 2024 |
| M B Commercial Services Ltd | Construction | 2024 |
| M B Media Limited | Information & communication | 2015 |
| M Brothers Civils Ltd | Construction | 2023 |
| M Buckingham & Company Limited | Construction | 2009 |
| M C Carpentery Ltd | Construction | 2024 |
| M Chowdhury Limited | Education | 2023 |
| M Croxford Ltd | Construction | 2014 |
| M D Healthcare Consultants Ltd | Administrative & support | 2005 |
| M Davis Construction Consultancy Limited | Other services | 2024 |
| M E Co Build Ltd | Construction | 2024 |
| M Edmunds Ltd | Financial services | 2024 |